Re: [PATCH][2.5] smp_call_function_mask

From: Zwane Mwaikambo (zwane@holomorphy.com)
Date: Tue Jan 21 2003 - 02:16:24 EST

On 20 Jan 2003, Alan wrote:

> On Fri, 2003-01-17 at 05:18, Zwane Mwaikambo wrote:
> > + /* Wait for response */
> > + while (atomic_read(&data.started) != num_cpus)
> > + barrier();
>
> Only old old intel x86 that does -bad- things as it
> generates a lot of bus locked cycles. Better to do
>
> while(atomic_read(&data.started) != num_cpus)
> while(data.started.value != num_cpus)
> {
> barrier();
> cpu_relax();
> }
>
> I would think ?

Cool, would a cpu_relax only be sufficient since that also has the memory
barrier?

        Zwane 

-- 
function.linuxpower.ca

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